Understanding the A1C Test: A Three-Month Picture of Your Blood Sugar

The A1C test—also known as HbA1c, glycated hemoglobin, or glycosylated hemoglobin—is a simple blood test that reflects your average blood glucose level over the past three months. It is one of the most important tools for screening, diagnosing, and monitoring diabetes and prediabetes, conditions that occur when blood sugar remains higher than normal.

How the A1C Test Works

To understand how the A1C test measures blood sugar, it helps to look at how red blood cells work. Most of the cells in your blood are red blood cells (RBCs), which are made in the bone marrow and carry oxygen throughout the body with the help of a protein called hemoglobin. Each RBC lives for about three months before being broken down and replaced.

Glucose—the main form of sugar in your blood—naturally attaches to hemoglobin in a process known as glycosylation. When blood sugar levels rise, more glucose sticks to hemoglobin molecules. The A1C test measures the percentage of red blood cells that have glucose attached, showing how much exposure your blood cells have had to glucose over their lifespan. In other words, the higher your A1C, the higher your average blood sugar during the past three months.

What the Results Mean

A normal A1C result indicates that your blood sugar is within a healthy range. If your A1C is higher than normal, it may suggest prediabetes or diabetes. For people already diagnosed with diabetes, a high result means blood sugar is not well controlled, and adjustments to diet, lifestyle, or medication may be needed.

Your healthcare provider may also use your A1C result to estimate your average blood glucose (eAG)—a helpful number that translates the percentage into the same units used by home glucose meters.

Who Should Take the A1C Test

Your doctor may recommend an A1C test if:

• You are over 45 years old

• You are under 45 but have risk factors for diabetes (such as being overweight, having high blood pressure, or a family history of diabetes)

• You had gestational diabetes during pregnancy

How the Test Is Done

During an A1C test, a healthcare professional collects a small blood sample from your arm or fingertip. The sample is then sent to a laboratory, where the amount of glucose bound to hemoglobin is carefully measured. Results are usually reported as a percentage, often alongside a chart that helps you understand how that percentage corresponds to your average blood sugar.

How Often to Get Tested

• People with diabetes: at least twice a year

• People with prediabetes: every one to two years

• Those with normal A1C but a history of gestational diabetes or risk factors: every three years

Regular A1C testing helps you and your healthcare provider track long-term glucose control and make informed decisions to prevent complications.

Reliable HbA1c Testing with Medlere Analyzers

At Medlere, we are committed to delivering accurate and efficient diagnostic solutions that empower healthcare professionals worldwide. Our range of analyzers offers multiple technologies for HbA1c testing:

• FiCA Immunofluorescence Analyzer – enabling rapid HbA1c testing in point-of-care settings.

• UClia POCT CLIA Analyzer – combining high sensitivity and convenience for on-site HbA1c analysis.

• M3 HPLC HbA1c Analyzer – providing gold-standard precision for laboratory-level HbA1c measurement.

Together, these systems help clinicians obtain reliable insights into glycemic control, supporting timely diagnosis and personalized diabetes care.